I have used the power analyzer to measure the power consumption, the average energy consumption per day is 675.775KWh/day.
to get the PV panel required for the system I multiply the daily consumption by 1.25 which is the 25% energy losses in PV system and after divided by the value of the sun peak hour that is 4.2 for Malakal town in South Sudan. the result is divided by 550Wp of PV panels that I have chosen which led to get 366 PV panels for the system.
in the same power analyzer data when I did the average maxim current, I found that for each phase we have 90A, to do the calculation I added 15% as a safety margin which gave me 103.5A/phase.
Now to size my battery bank, this is how I started. Based on the average max current plus the safety margin, I used this formula to determine the max active power used in real time by the system. P = I X 554.25
P = 103.5X554.25 = 57364.875 W, 57.364KW
P= 54.364KW
Knowing the active power, I time by 24house to get the maximum energy consumption per day; and here is the result,
E= 54.364 X 24 = 1304.736KWh/day
Now the formula for the battery sizing that I have used is that:
Battery bank (Ah) = 1304.736KWhX1day of autonomy/ (0.85X0.8X52)
0.85 Batteries losses, 0.8 battery efficiency and 52 batty bank setups. I have used the freedom won Lite 60/48 for this purpose.
Battery bank(Ah) = 36898.64Ah this is the battery bank capacity needed to hand load.
to get the quantity of battery needed
No of the batteries = 36898.64Ah/1200 = 30.74
No of Lite 60/48 battery will be 31 Pcs.
now in the datasheet of the battery it recommends maxi 35KVA inverter, which mean for each battery we will need 2 Quatro 15KVA.
Please if I am wrong help be determine the battery bank and the inverter/charger;
for the system I want to used fronius both in the input and output.
The other information is that the maxi load is during the night from 6PM to 7am. during the day the average max current is around 60A/Phase.
Please help me clarify this design.
Look forward to hearing from you.
